Cheilanthes - Sinopteridaceae

Cheilanthes involuta (Sw.) Schelpe & N.C. Anthony var. obscura (N.C. Anthony) N.C. Anthony

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Zimbabwe

 

 

 

 

Synonyms

Cheilanthes involuta (Sw.) Baker var. obscura (N.C. Anthony) N.C. Anthony
Pellaea viridis (Forssk.) Prantl var. involuta sensu Schelpe and sensu W. Jacob and sensu Kornas
Cheilanthes viridis (Forssk.) Sw. var. obscura N.C. Anthony
Pellaea involuta (Sw.) Bak. var. involuta (N.C.Anthony) Verdc.

Common name

Description

Rhizome shortly creeping to ascending, c. 4 mm in diameter; rhizome scales linear-lanceolate in outline, apex gradually tapering to a point, margin entire, sometimes minutely toothed, 3–6 mm long, pale reddish brown, sometimes with a dark central stripe. Fronds monomorphic, tufted, 10-40 cm long, herbaceous to coriaceous. Stipe 2–15.5 cm long, purplish black, grooved, sulcus flat to square in cross-section, densely hairy and covered with brown or blackish scales up to 3 mm long. Lamina 2-pinnate to 3-pinnatifid, ovate to subdeltate or more triangular in outline with the basal pinnae the largest, usually basiscopically developed, 3–24 x 2.2–13 cm; pinnae 4–12 pairs; ultimate pinnules oblong, oblong-ovate or oblong hastate in outline, 10–20 x 6–12 mm, with crimped edges, upper surface glabrous, costules below with a few scales; veins free, obscure or ± visible; rhachis and secondary rhachises set with numerous or scattered lanceolate brown hair-like scales, grooved above, sulcus flat to square in cross-section. Sori linear, marginal; indusium continuous, suberose.

Notes

May be confused with C. viridis var. glauca which differs in having a rhachis that is deeply grooved, an almost black stipe and veins that are clearly visible. Differs from C. involuta var. involuta by having a more triangular lamina, basal pinnae that are the largest and a sulcus that is flat to square in cross-section.

Derivation

involuta: inrolled, referring to the sometimes inrolled pinnule margin; obscura: obscure, venation not being very visible.

Habitat

Boulder bases and among rocks in woodland and grassland, stony places on lava hillsides, crevices in granite rocks.

Distribution worldwide

African, Madagascar, Socotra.

Distribution in Africa

Angola, Botswana, Dem. Republic of Congo, Kenya, Lesotho, Mozambique, Namibia, South Africa, Tanzania , Uganda, Zambia, Zimbabwe.

Growth form

Lithophytic, terrestrial.

Literature

  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Page 145. (Includes a picture).
  • Crouch, N.R., Klopper, R.R., Burrows, J.E. & Burrows, S.M. (2011) Ferns of Southern Africa, A comprehensive guide. Struik Nature. Pages 386 - 387. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 287 - 288. As P. viridis var. involuta (Sw.) Schelpe (Includes a picture).
  • Kornas, J. (1979) Distribution and ecology of the Pteridophytes in Zambia. Polska Akademia Nauk Wydzial II Nauk Biologicznych. Page 59. As P. viridis var. involuta (Sw.) Schelpe
  • Roux, J.P. (2009) Synopsis of the Lycopodiophyta and Pteridophyta of Africa, Madagascar and neighbouring islands. Strelitzia 23, South African National Biodiversity Institute, Pretoria. Page 183.
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta. Southern African Botanical Diversity Network Report, 13 Page 64.
  • Schelpe, E.A.C.L.E. (1970) Pteridophyta. Flora Zambesiaca, 0 Page 136. As P. viridis var. involuta (Sw.) Schelpe
  • Verdcourt, B. (2002) Adiantaceae. Flora of Tropical East Africa, Pages 17 - 18. As Pellaea involuta (Sw.) Bak. var. obscura (N.C.Anthony) Verdc.
  •